SmartDNS是推荐本地运行的DNS服务器，SmartDNS接受本地客户端的DNS查询请求，从多个上游DNS服务器获取DNS查询结果，并将访问速度最快的结果返回给客户端，提高网络访问速度和准确性。 支持指定域名IP地址，达到禁止过滤的效果。
一 安装smartdns
1 关闭Ubuntu自带dns解析systemd-resolved
#查看端口
sudo netstat -lnp|grep 53
tcp 0 0 127.0.0.54:53 0.0.0.0:* LISTEN 698/systemd-resolve
tcp 0 0 127.0.0.53:53 0.0.0.0:* LISTEN 698/systemd-resolve
udp 0 0 127.0.0.54:53 0.0.0.0:* 698/systemd-resolve
udp 0 0 127.0.0.53:53 0.0.0.0:* 698/systemd-resolve
raw6 0 0 :::58 :::* 7 553/systemd-network
unix 2 [ ACC ] STREAM LISTENING 9453 924/systemd /run/user/1000/pk-debconf-socket
#关闭
sudo systemctl disable systemd-resolved
sudo systemctl stop systemd-resolved
2 安装 smartdns
sudo apt update
sudo apt-get install smartdns
#查看版本
test@test:~$ smartdns -v
smartdns 45+dfsg-1build2
#启动
sudo systemctl enable smartdns
sudo systemctl start smartdns
二 配置smartdns
sudo vim /etc/smartdns/smartdns.conf
#接口绑定信息
bind-tcp [::]:53
bind :53
#开启过期缓存
serve-expired yes
#过期时间
serve-expired-ttl 0
#缓存数量
cache-size 68888
#域名TTL最小值和最大值
rr-ttl-min 60
rr-ttl-max 866000
# 上游DNS返回多个结果时，测速的方法
speed-check-mode tcp:80,tcp:443,ping
#日志记录等级（warn，info，debug）
log-level info
log-file /var/log/smartdns/smartdns.log
log-size 2m #日志大小
log-num 1 #日志归档个数
#配置上游dns服务器
#阿里dns
server 223.5.5.5
server 223.6.6.6
#腾讯dns
server 119.29.29.29
#配置server的组关系
server 8.8.8.8 -group google -exclude-default-group
server 8.8.4.4 -group whatsappdns -exclude-default-group
server-tcp 8.8.4.4
#配置address,解析指定的域名和IP
address /www.test.com/192.168.50.13
三 测试验证
1 ubuntu 系统
#第一次查询
test@test:~$ dig www.csdn.net
; <<>> DiG 9.18.24-0ubuntu5-Ubuntu <<>> www.csdn.net
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 32569
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 0
;; QUESTION SECTION:
;www.csdn.net. IN A
;; ANSWER SECTION:
www.csdn.net. 3 IN CNAME 55cb88f4.csdn.net.cname.yunduns.com.
55cb88f4.csdn.net.cname.yunduns.com. 3 IN A 220.185.184.18
;; Query time: 532 msec
;; SERVER: 127.0.0.53#53(127.0.0.53) (UDP)
;; WHEN: Sat Jun 01 17:45:37 CST 2024
;; MSG SIZE rcvd: 95
#第二次查询
test@test:~$ dig www.csdn.net
; <<>> DiG 9.18.24-0ubuntu5-Ubuntu <<>> www.csdn.net
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 36998
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 0
;; QUESTION SECTION:
;www.csdn.net. IN A
;; ANSWER SECTION:
www.csdn.net. 32 IN CNAME 55cb88f4.csdn.net.cname.yunduns.com.
55cb88f4.csdn.net.cname.yunduns.com. 32 IN A 220.185.184.18
;; Query time: 0 msec
;; SERVER: 127.0.0.53#53(127.0.0.53) (UDP)
;; WHEN: Sat Jun 01 17:46:05 CST 2024
;; MSG SIZE rcvd: 95
#测试域名查询
test@test:~$ dig www.test.com
; <<>> DiG 9.18.24-0ubuntu5-Ubuntu <<>> www.test.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 41058
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0
;; QUESTION SECTION:
;www.test.com. IN A
;; ANSWER SECTION:
www.test.com. 60 IN A 192.168.50.13
;; Query time: 0 msec
;; SERVER: 127.0.0.53#53(127.0.0.53) (UDP)
;; WHEN: Sat Jun 01 17:49:50 CST 2024
;; MSG SIZE rcvd: 46
2 windoes 11系统
